This invention relates to a parachute collision avoidance system in an emergency aircraft ejection system.
The problem of collision between a crewmember and the ejection seat, and between the ejection seat and a subsequently ejected crewmember, exists in emergency aircraft ejection systems.
Various systems have been devised to overcome these collision problems. In some of the early ejection systems wherein the crewmember's parachute was deployed after seat separation, parachutes have been used for seat stabilization prior to seat separation and for aiding in the separation of the crewmember from the seat. These parachutes, if used where multiple ejections are employed, would also inherently retard the seat to aid in the avoidance of collisions between the seat and a subsequently ejected crewmember.
Due to the need for more rapid deployment of the crewmember's parachute, systems are needed which permit the recovery of crewmembers under a larger range of adverse conditions and at lower altitudes. Ejection systems have been devised wherein the crewmember's parachute is deployed before seat separation. Conventional parachutes, provided to aid in seat separation, cannot be used in these systems due to the problem of entanglement between the two parachutes. In these systems which use seat stabilization parachutes, the seat stabilization parachute must be cut loose prior to deployment of the crewmember's parachute to avoid parachute entanglement problems. With the parachute cut loose prior to the deployment of the crewmember's parachute, the inherent seat retardation, to prevent collision between the seat and subsequently ejected crewmember, is lost.
With the continuing requirements for reducing sequencing time delays in the recovery of crewmembers, from aircraft which are in adverse altitudes at the time of egress initiation, some means is needed for reducing the collision problems in emergency ejection systems which use crewmember parachute deployment prior to seat separation.